Google, Yahoo, MSN Search and all the other search engines on the net use bots to fish the net constantly. Usually about every 24-36 hours if I remember correctly the whole net is redone.. may have been speeded up. To get the really quick results when you enter a search string, it is because of these fishing expeditions the bots do and the data they harvest.

These bots are basically harmless. It is the spambots and other malware that really can cause problems. Seeing these bots now is informative.. I kinda like it.